Which NATO VTOL is Better ?

Michel Van

Michel Van

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In 1960s NATO show interest in VTOL jets for fighter and reconnaissance plane
it's member start R&D for proposal and prototype
most design (EWR VJ-101D, Dassault Mirage IIIV, Fiat G95) used lift engines
the EWR VJ-101C used rotating engines in nacelles at the wingtips and lift engines
While P.1127, P.1145, VFW VAK 191 used pegasus engine with four moving vectoring nozzles.
But in end NATO lost interest in VTOL, Labour government, led by Harold Wilson murder P.1154 program and other country stop the R&D begin of 1970
ironical the HSA P.1127 survived as Harrier what had a extraordinarily career, even exported to USA (take that Wilson !)
In Falkland war, the Harrier show marvelousness maneuvering during dog-fight against Argentina Mirage fighter.
thank to pegasus engine with four moving vectoring nozzles

I wonder had the VTOL with lift engines or rotating engines, the same marvelousness maneuvering of the Harrier ?
or are the P.1127 and supersonic P.1145 concept the ultimate VTOL ?
 
Michel Van said:
In Falkland war, the Harrier show marvelousness maneuvering during dog-fight against Argentina Mirage fighter.
thank to pegasus engine with four moving vectoring nozzles - Not really - tail chases were the main mode of engagement. VIFF was not used.

I wonder had the VTOL with lift engines or rotating engines, the same marvelousness maneuvering of the Harrier ? No!
or are the P.1127 and supersonic P.1145 concept the ultimate VTOL ? P.1127 was. For P.1154 see link below!
Click to expand...
 
Michel Van said:
... In Falkland war, the Harrier show marvelousness maneuvering during dog-fight against Argentina Mirage fighter.
thank to pegasus engine with four moving vectoring nozzles ...
Click to expand...

What I've read so far (e.g. in Robert Jackson "Sea Harrier and AV-8B") is, that "viffing" actually wasn't
used during the Falklands conflict, but during flight tests and mock-combat at best.

Michel Van said:
... VFW VAK 191 used pegasus engine ...
Click to expand...

The VAK 191 used a [font=verdana, arial][SIZE=-1]Rolls-Royce/MTU RB 193-12 engine with thrust-vectoring (this engine actually
led to a patent infringement suite by Bristol-Siddeley against RR ..) and two lift-engines. IIRC it's main
raison d'etre was replacing the F-104G in the "special weapons delivery" role, increasing survivability
by flying low and fast and being independent from runways. So, manoeuvrability wasn't much of a
design point and the overall philosophy was, that use of a vectored thrust engine alone was unecono-
mical. And carrying of weapons on wing hardpoints wasn't originally envisaged at all. That was not done
before the appearance of the VAK 191B. Mk.2, but the VAK 191 remained more or less a VTOL aircraft,
whereas most airforces already were interested much more in STOVL, as proven by the Harrier.
Quite a good article (although probably as biased as such articles always are ... [/SIZE][/font] ;) ) can be found in
Air Enthusiast, April 1972 issue.
 
Michel Van said:
I wonder had the VTOL with lift engines or rotating engines, the same marvelousness maneuvering of the Harrier ?
or are the P.1127 and supersonic P.1145 concept the ultimate VTOL ?
Click to expand...

With lift engines, you'd have to start them beforehand and keep them running until the end of the fight, this means lots of extra fuel consumption. Also, controlling the thrust is awkward since the lift engines are at a fixed angle.
With rotating engines you could do the same as with the nozzles, but it'd take a bit longer to rotate because you're moving a much larger item.

According to this video:
https://www.youtube.com/watch?v=LqV4YKMMkUk&feature=player_embedded#!

the Harriers did use vectoring and other low-speed tactics in the Falklands.
(adm, Nigel Ward, at 30:00)
 
Hobbes said:
According to this video:
https://www.youtube.com/watch?v=LqV4YKMMkUk&feature=player_embedded#!

the Harriers did use vectoring and other low-speed tactics in the Falklands.
(adm, Nigel Ward, at 30:00)
Click to expand...

Ok, that's a better proof, than an author, who probably wasn't actually on the scene, I think.
And I have just read a page in Andrew Dow's "Pegasus-Heart of the Harrier" again. There's an incident
mentioned, when Lt.Cdr. D. Morgan used vectoring the nozzles downward to slow his descent, when trying
to catch an Argentine Pucara, he had attacked from great height. And the same pilot used vectoring for
avoiding two Roland missiles, so that Andrew Dow wrote "It is often said, that viffing was not used in the
Falklands conflict, because it did not involve air-to-air fighting, but Lt.Cdr. D. Morgan's use of the nozzles of the
Pegasus came very close to it." So, you are right, I was wrong, sorry !


Hobbes said:
With lift engines, you'd have to start them beforehand and keep them running until the end of the fight, this means lots of extra fuel consumption. Also, controlling the thrust is awkward since the lift engines are at a fixed angle.
Click to expand...

Lift engines are shut-down just after transition to conventional flight (when intakes and exhausts
are shut !), so it's generally only a short time, they are running and the main engine can be smaller
and (hopefully !) consuming less fuel, than in a vectored-thrust-only design. The admirers of the lift/
lift-cruise layout always stress the point, that for a vectored-thrust-only design, the engine actually
is oversized. And in the VAK 191B, the lower engine doors acted as a crude deflector, giving at least
some means of thrust-vectoring for the lift-engines, too, and it was claimed, that they even gave a
"bring-me-home" capability in the event of a break-down of the main engine.
It's clear, that the VAK 191 didn't reach a similar STOVL performance, as the Harrier, but it should be
remembered, that it originally wasn't designed that way.
 

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